Malaria

Malaria is a disease caused by the parasite Plasmodium, which is transmitted by the bite of an infected mosquito. Only the Anopheles genus of the mosquito can transmit Malaria. The symptoms of the disease include fever, vomiting, and/or headache. A characteristic malarial fever has ‘hot', ‘wet', and ‘cold' phases and appears 10 to 15 days after the mosquito bites. To diagnose malaria, blood slides are examined under a microscope, where the parasite is seen inside red blood cells. Rapid diagnostic test kits (RDTs) are used for diagnosing malaria in remote areas where microscopes cannot be used. 

Plasmodium vivax or P. falciparum are the most common malarial parasites, while P. malariae and P. ovale are other rarer forms. Of these, infection with P. falciparum is the most fatal if left untreated, possibly leading to kidney and brain complications, and even death. Chloroquine was the treatment of choice for malaria and is still followed in most countries for treatment of P. Vivax, but P. falciparum has developed resistance to it. As a result, Artemisinin-based combination therapy is now presently advised as the primary treatment for malaria. Among preventive measures, the use of insecticide treated nets at home and indoor residual spraying of insecticides are recommended for malaria. These precautions act by decreasing exposure to bites of infected mosquitoes. 

Key facts
  • Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected mosquitoes.
  • A child dies of malaria every 2 minutes.
  • In the Americas, 765,000 cases of malaria and around 340 deaths were reported in 2018.
  • In 2017 there were 219 million cases of malaria globally, causing nearly 435,000 deaths, mostly among African children.
  • Malaria is preventable and curable.
  • Approximately half of the world's population is at risk of malaria, particularly those living in lower-income countries. In the Americas, 138 million people live in areas at risk of malaria.
  • Travelers from malaria-free areas to disease "hot spots" are especially vulnerable to the disease.
  • Malaria takes an economic toll - cutting economic growth rates by as much as 1.3% in countries with high disease rates.


There are four types of human malaria:

  • Plasmodium falciparum
  • Plasmodium vivax
  • Plasmodium malariae
  • Plasmodium ovale

Plasmodium falciparum is the most deadly. In the Americas, 77% of the infections are due to Plasmodium vivax.

What PAHO does
  • In 2016, PAHO/WHO Member States approved the resolution CD55.R7, Plan of Action for Malaria Elimination 2016-2020, through which they are committed to continue reducing malaria cases over the next four years. This plan also seeks to prevent the reestablishment of the disease in 27 countries and territories of the Region that have been considered malaria-free since early 1970s.
  • PAHO/WHO works with the governments, nonprofit organizations, initiatives and networks that support efforts in the Americas for the control and elimination of malaria: Amazon Network for the Surveillance of Antimalarial Drug Resistance and Malaria Champions of the Americas.

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